1. Field of the Invention
The present invention relates to a filter for liquid metals comprised of alveolar or honeycomb ceramic material, a process for the preparation thereof and its use in the filtration of liquid metals or alloys having very high melting points, such as steels, cast iron and refractory metallic alloys.
2. Description of the Prior Art
It is known to this art to use filters of alveolar ceramic materials based on zirconia or alumina for the filtration of liquid metals or alloys having very high melting points.
Such filters have the disadvantage of being excessively burdensome and often suffer from thermal fragility.
It is also known, in the automotive industry, to use less costly filters of cordierite, or an alveolar cordierite/mullite mixture, in the form of discs or foams. However, application of such filters are limited to a temperature of approximately 1,500.degree. C., meaning that they cannot be used for filtration of molten steels which require a temperature of about 1,650.degree. C.